What do you think?
Screen Capture in OS X
OS X has a built-in screen capture tool that can also be used to give you measurements/co-ordinates. It is really handy for quickly getting the distance between objects on your screen, like columns in web pages for example.
To invoke the tool, use the the keys cmd + shift + 4. If you don’t want to take a screen grab just press the escape key.
This is great for quick snaps and measurements, but I use Snapz Pro for most things. It has the best options for borders, file types and offers video capture too. You can also choose from objects, full screen and where to save your files. The Ambrosia website offers a free trial, so hop over and check it out: http://www.ambrosiasw.com/utilities/snapzprox/other page